An E&E Special Report

E&E explores the science, politics and policy of climate change in this ongoing special report. The report is broken into three distinct sections: domestic policy, international action, and science and technology. Click on a header below to go to a specific section.

Brace yourself for a long series of congressional hearings on global warming.

There'll be climate models sprawling over decades, emissions inventories that go from coal-burning power plants to grass-munching cows, calculator-crushing economic impacts that soar into the trillions and dueling experts.

So many numbers, so many dollar signs. No wonder so many Washington wonks are wild for climate "stabilization wedges."

Two Princeton professors coined the term a couple of years ago as the simplest way to deconstruct what must be done to avert catastrophic climate chaos. Robert Socolow and Stephen Pacala, who outlined the concept in the journal Science, didn't invent the idea of an energy portfolio, but their way of linking it to global warming and all its complications seem to have hit on something big.

Here's how it works: Start with a toolbox of 15 energy technologies and lifestyle choices. Choose seven to implement. If these "wedges" -- as the profs call the emission-cutting tools -- are all carried out with gusto around the world for 50 years, the soupy mix of gases heating the earth's atmosphere may be on the way to slowing, stopping or even reversing their current trajectory.

Critics of the wedges warn they are an over-simplified academic exercise unconstrained by price tags or real-world politics. But a growing number of politicians, teachers, lawyers, industry lobbyists and environmentalists consider the concept a great way to identify and articulate their climate strategies.

(Above) Carbon emissions from fossil fuels are projected to double in the next 50 years, a path (black line) that scientists predict will lead to significant global warming by the end of the century. Keeping emissions stable (orange line), followed by reductions in the second half of the century could negate some problems. Achieving the "stabilization triangle" requires curbing carbon dioxide emissions by about 7 billion tons a year by 2055. (Below) The Stabilization Triangle is sliced into seven wedges, with each the same as avoiding 1 billion tons of CO2 emissions per year by 2055.

"The wedges concept is sort of the iPod of climate policy analysis," said David Hawkins, climate director at the Natural Resources Defense Council. "It's an understandable, attractive package that people can fill with their own content."

Wedges are the backbone of climate solutions offered by former Vice President Al Gore at the end of the Oscar-nominated documentary "An Inconvenient Truth." Ken Connolly, who was staff director for former Sen. Jim Jeffords (I-Vt.), tacked a wedges poster on his office wall as he worked on global warming legislation during the 109th Congress.

And leading Democrats and some Republicans have suggested the wedges fit into their legislative plans.

"Don't expect one giant bill on energy or one giant bill on global warming," said Sen. Barbara Boxer (D-Calif.), chairwoman of the Environment and Public Works Committee, in a recent interview. "More than likely, there'll be a number of bills that address the question of global warming."

Senate Majority Leader Harry Reid (D-Nev.) referenced the concept during a speech earlier this month at the National Press Club. He said his committee leaders would work on bills that expand the federal fleet of renewable vehicles, establish mandates for buildings that use energy efficiently and increase fuel standards for motor vehicles -- all of which fit into the Socolow-Pacala philosophy.

"I find it astonishing, even without acknowledging where they got it, people talk about wedges," said Jonathan Lash, president of the World Resources Institute.

The wedges have also become a role-playing game, giving people with diametrically opposing points of view a chance to sit at the same table and come up with solutions to combat climate change. Socolow and Pacala are working with designers on a version of the game for teachers (see sidebar).

"It gets people talking and having conversations about their own ideas," said Sarah Wade, a consultant in Washington who has helped organize a half-dozen wedge games around the country. "It forces you to put on someone else's shoes."

Potential Wedges Chart

About This Report

E&E senior reporter Darren Samuelsohn explores "The Stabilization Wedges" -- a way of thinking about global warming crafted by a pair of Princeton professors. The concept has been adopted by a growing number of politicians, teachers, lawyers, industry lobbyists and environmentalists who are using it to articulate their own climate strategies.

'Wedges' -- the game: Coming soon to a classroom near you

The "wedges" game wasn't designed to juice up a Saturday night.

It's a role-play diversion aimed at teaching players about the complexities of global warming. And people who've played wedges in meeting rooms and classrooms say it does just that.

"It made them think outside of who they were, and what their special interests were," said Susan Capalbo, an economics professor at Montana State University, who led a game with her undergraduate students last fall.

Players from Greenpeace and the Nuclear Regulatory Institute sifted through their differences at a Washington, D.C., wedges game in the summer of 2005. Organizers can count more than a dozen wedge games played over the last three years.

In a typical game, players form teams of four or five. Each team chooses seven wedges (each representing an energy technology or policy ) out of a portfolio of 15 (To see the complete list, click here).

Judges weigh each team's choices and declare a winner. Most games last about 90 minutes to two hours.

Sarah Wade, a Washington-based consultant who has organized about a half dozen wedge events, said the games help people understand that climate change can't be solved by focusing on one technology. It also forces participants to think outside of their comfort zone, selecting nuclear power, for example, over wind energy.

"Inevitably, someone has an option they put forward, but they don't really like it," Wade said. "That's one of the messages about climate change. This isn't going to be an easy thing to fix. We're not going to like all the things we have to do. But what are the best ones given what you want to achieve?"

The wedges' creators, Princeton University professors Stephen Pacala and Robert Socolow, wrote about the concept in an academic paper. They turned their idea into a game to serve as an icebreaker at a conference. They have since teamed up with BP and Ford Motor Co., with the intention of developing educational materials for high schools.

About 500 teachers will get a lesson in how to use the wedges during the annual American Association for the Advancement of Science conference next month in San Francisco.